Winemaking procedure in which a product is added to wine in order to remove unwanted material. Typical fining agents include bentonite clay (to remove proteins) and egg white (to remove bitter tannins). Ox blood was once commonly used as a fining agent but is now generally forbidden.

Usually sweet wine, in which the alcoholic fermentation is stopped before all the sugar has been consumed, by the addition of brandy. The alcohol kills the yeast, leaving a sweet wine with high alcohol. Examples include Port and Vin Doux Naturel. Sherry, by contrast, is fortified after fermentation, and so it is naturally dry.